Design of a compact omni-directional ENG ZOR antenna

Abstract

A negative permittivity (ENG) zeroth-order resonance (ZOR) antenna with compact size and low profile is introduced in this paper. By adding a shorting via and applying capacitive coupling feeding technology, the antenna could operate in the center of f₀ =5.084GHz, which is corresponding to the electric size 0.273λ₀×0.273λ₀×0.0136λ₀ (where λ₀ is the wavelength corresponding to the operational frequency f₀ in free space). The equivalent circuit model is presented to explain the physical phenomenon accordingly.